Over the last 20 years, Ray Blanchard, Ph.D., with a variety of coauthors and collaborators, has proposed a theory that links the sexual orientation of male-to-female transsexuals with the presence or absence of autogynephilia (erotic arousal by the thought or image of "himself" as a woman). Blanchard's Autogynephilia Theory suggests that the association between sexual orientation and autogynephilia among male-to-female transsexuals is clinically important and the association is always (or almost always) present. Although the theory has been criticized by clinicians, researchers, and transsexuals themselves, it has not been critiqued in a peer-reviewed article previously. This article will attempt to fill that gap. Key studies on which the theory is based will be analyzed and alternative interpretations of the data presented. I conclude that although autogynephilia exists, the theory is flawed.